This year, global leadership will be tested like never before.

Significant progress has been made in the past decade. Global poverty rates are falling. Child and maternal mortality rates are down, many more children are in school, and the total number of people going hungry in the world is falling – albeit far too slowly.

Yet extreme economic inequality is out of control and getting worse. From Ghana to Germany, South Africa to Spain, the gap between rich and poor is rapidly increasing. At the World Economic Forum last year, Oxfam released a statistic that made headlines: 85 rich individuals held more wealth than the poorest half of the world’s population – 3.5 billion people. Now, a year later, that figure has become more extreme – 80 billionaires have the same amount of wealth as the bottom half of the planet.

Across rich and poor countries alike, this inequality is fuelling conflict, corroding democracies and damaging growth itself. Not long ago those who worried about inequality were accused of partaking in the politics of envy. In the past year this concern officially became mainstream as voices from the Pope to Christine Lagarde to President Obama cautioned of its impacts. The mounting consensus: left unchecked, economic inequality will set back the fight against poverty and threaten global stability.

At the same time, the impacts of climate change are exacerbating this growing divide. As temperatures rise, extreme weather events are becoming more frequent and severe, crops and livelihoods are being devastated, and the efforts of people on low incomes to feed their families are being undone. Those who are least to blame are suffering the most.

Rising inequality and climate change: these are the defining challenges for 2015. This is the year when we will have to set a course for action for a sustainable and just world.

Winnie Byanyima 2

An action plan

What action can we take? These profound global challenges require bold responses.

In October last year, Oxfam launched a global campaign to tackle inequality, Even It Up, in which we pledged to campaign for years to come on a seven-point plan to close the gap between the rich and poor, focusing on measures ranging from public financing for free health and education, to decent work and wages and political participation for all.

This year, our collective energy must focus first on international tax reform. To make headway on tackling inequality, a more ambitious, far-reaching and inclusive process is needed to fix the broken international tax system, to prevent corporations from dodging the taxes they owe and to give governments the resources they need to tackle poverty and inequality. Yesterday’s international tax system is not fit for purpose – let alone fair – today. The year 2015 must be when world leaders rewrite fragmented global tax rules that reward those who avoid their civic obligation, and leave the poorest to foot the bill.

For this reason, Oxfam is calling for a world tax summit in 2015, which would allow a discussion between all countries, rich and poor, to set the basis for a permanent body to set, implement and arbitrate fairer international tax rules.

On climate change, 2015 could be a pivotal year if our leaders rise to the challenge. Last year we saw the latest scientific assessments confirm more clearly than ever the scale of the danger we face from a warming world. And we saw the response of citizens: in September in New York, l joined a hundreds of thousands on a march to demand real action on climate. We were joined by many thousands more in other cities worldwide.

This year, governments have a chance to secure an agreement at the UN that could be a turning point in the fight to cut and ultimately end greenhouse gas emissions, and secure the support vulnerable communities need to adapt to climate change.

In recent months private companies have made some encouraging climate pledges and commitments to clean energy. But ultimately, governments must lead and act on the issues that most affect citizens and our planet. Only with political leadership can we get the global action that a growing number of people around the world are demanding.

In Davos, I look forward to a robust and frank discussion about these issues, which challenge vulnerable communities and powerful businesses alike.

Author: Winnie Byanyima is Executive Director of Oxfam International and a Co-Chair at this year’s Annual Meeting of the World Economic Forum in Davos.

Winnie Byanyima is attending our Annual Meeting 2015 in Davos, and is a panel member in the sessions, The BBC World Debate: A Richer World, but for Whom? on 23/1 at 9am CET and The Global Agenda 2015 on 24/1 at 4.45pm CET.  

Image: A view of the Turano slum in Rio de Janeiro March 11, 2014. REUTERS/Sergio Moraes